Start by peeling the russet potatoes and cutting them into small cubes. This will help them cook evenly and mash easily.
Place the cubed potatoes in a large pot, cover them with water, and add a pinch of salt. Bring the water to a boil and cook the potatoes for about 15-20 minutes or until fork-tender.
Once the potatoes are cooked, drain them in a colander and return them to the pot. Using a fork or a potato masher, mash the potatoes until they are smooth. Season with salt and pepper to taste.
In a frying pan or skillet, heat a small amount of vegetable oil over medium heat. Once hot, add a tortilla and cook for about 30 seconds on each side until golden and pliable. Repeat with the remaining tortillas, adding more oil as needed.
Spoon a generous amount of the mashed potatoes onto each tortilla. Sprinkle with shredded queso fresco and any additional toppings you desire.
Serve the potato tacos warm, garnished with your choice of toppings like fresh cilantro, salsa, or avocado. Enjoy your delicious creation!